Shock-absorber.



A, Looms. SHOCK ABSORBER. APPLICATION FILED DBC. 4, 1908,.

Patented May 28, 1912] 2 SHEETS-SHEET 7.

e. J. @geb wsa )mi A. LDOMIS.

SHOCK ABSORBER. APPLIOATIQN FILED Dnc. 4, 190e. 19027966@ ,Y Patented May 28, 1912. 2 gums-'SHEET 2:

i tionv will appear in the detail description 5 gan, have invented certain new and use'tul Improvements in Shock-Absorbeisof which [the .following is a specification. I. This invention relates to improvements in v`-devices` for relieving the shock due to the relative vibration between the body or frame Q of avehicle and its axle when the vehicle is moving over rough or uneven surfaces, and it is particularly adapted for use on motor vehicles.

More particularly this invention relates to` shock absorbers or spring dampeners producing little or no resistance in the middle portion of their range of action and an increasing resistance. toi ard both ends of the range; and it. further lates to means for automatically shifting thmiddle point of least resistance'v of the s ook absorber to correspond with diferent positions of the" vehicle parts due to change'ot load,

Thev objects and advantages of the invenollowing.

In the accompanyingdrawings, Figure 1 is a sideelevation of yso much of a motorl vehicle as is necessary to illustrate the 1nventin, andl one form of the invention is shownattached to such parts; Fig. 2 is a view similar to Fig. l and showing'the 'invention applied in another form; Fig. 3 is `a section on the line 3-'-3 of Fig. 2; Fig. 4

is an' enlarged section onthe line 4-4 of Fig. 1; and Fig. 5 is a section on the line 5-5 of Fig. 4.

As suggested hereinabove, this invention 4.0 isparticularly applicable to motor vehicles,

in which considerable spring laction is desirable, thus necessitating the use of springs loaded to nearly their maximum .capacity, andjer this class of vehicles many types of shock absorbers or spring dampeners` {fragment of one of the side members of a ;.,v ehicle frame, .2 is one of the axles of the vehicle, and is a fragment of one of the have beendevisecl to save the springs from .too sudden orviolent displacement at either end of their range of action, thus preventing spring breakages and greatly increasing the comfort of the passengers of the vehicle.

Ampng these manyv devices is a general typeA having a point approximately at the middle of its range of action in which there'sistance 'to the spring action is ata miniinm and.,

ALLEN Loomis-0E DETROIT, MICHIGAN, Assreivoa- BY MESNE ASSIGNMENTS, To THE .racxami Moron CAR coMrANY, or DETROIT, MICHIGAN, a coaroaATioN or MIQHIGAN.

SHOCK-Assmann.

Specication of Letters Patent. Application tiled December 4J 1908. Serial No. 465,924. I,

Patented May 28,1912.

the vehicle this point is of course arranged to correspond with the mean position of the vehicle parts with a normal load on the body of said vehicle. Thus with such normal load the resistance of the shock absorber to the vehicle spring action is the same in either direction of such action, but if the vehicle is overloaded or is lighter than normal, vthe relation of the point of least resistance of the shock absorber to the mean position of the vehicle parts is altered and the jshock absorber th'en resists the action ot' the vehicle' spring more in .one direction than in the other. This is sometimes mitigated in this class of absorber by the provision of means for' rendering considerable ot'tthe middle portion of therange of operation oi the 'shock absorber inactive so that there is no resistance to the action of the vehicle spring until saidV spring jnearly reached its limit in either direction.

Of course it is advisable to allow a slight unrestricted movement ot' the vehicle spring at both-.sides of its mean center of action, vbut itwill readily be seen to be an important object to have this mean position always corresponding' with the 4middle point of 'least resistance of the shock absorber, whereby an equal resistance tothe vehicle spring 'isobtained in both directions of movement. By the present invention this object is automatically attained, the middle point of least resistance ci' the shock absorber always re maining constant with the mean position of' the vehicle parts. f

The structures herein shown cally maintaining the point of least resistance 'of they shock absorber in correspondence with the mean position of the vehiclel parts constitute thepreferred embodimens of the inventiom but it will be understood thatmany 'other constructions may be used without departing from the spirit of the invention.

Referring to the drawings,.1 designates a springs which yieldably supports the frame from the axle, thus permitting relative vibratory movement between the axle and the frame.

'Referring 'particularly'to the form of the invention illustrated in Figs. 2 and 3, a

for automatiis represented by the members 4 and 5 hinged together at with the free end of the member 4 pivotally hung at 7 from a bracket 8 on thc frame 1 of the motor vehicle, and with the arm 5 pivotally hung at gether by springs 18 surrounding the posts with the member 5 3, or 1t may be separately constructed and 19, which are supported by one of the plates, the tensions of these springs being adjustable by nuts 20. The posts 19 are preferably enlarged fas at 2l between the plates so thatthe action of the springs 18 Will' be nullitied for a short distance near the middle of the path-,of travel of the friction plates along the sides ofthe Wedge piece 17. 'lhusthere is no resistance to the action of the spring 3 for a slight distance at each side of its mean center of4 vibration. Une 0f the plates 14, 15, may be formed integral as shown in Figs. 2 and suitably secured thereto.

If the free end of the member 5 were directly pivoted to the bracket 10 as in most shock absorbers of this type, any overload- `ing or lightening of the vehicle would cause a shifting of the ine-in position of the axle 2 relative-to the frame 1, and thismean position 'would not then correspond with the middle point of least resistance of the shock absorber and the consequent resistance of the absorber in one direction would be greater than in the other. But by pivoting the member 5 to the bracket 10 through a dash pot 22 or an equivalent sluggish retarding device, if the vehicle is overloaded, the resistance of the shock absorber to the first few relative vibrations of the axle will begreater in one direction than in the other -which will cause the cylinder 23 of the dash pot 22 to rise slowly relative to the piston 24 whereby the altered mean position of the axle will soon again correspond with the middle point of least resistance of the shock absorber, and this automatic adjustment will again'take .place Whenever the load on the vehicle body is charged. It will of course be understood that the space in the cylinder 23 ofthe dash pot is filled with a very heavy oil or grease, preferably an extremely thick graphite grease, and the piston 24 has a small passage 25 formed therein, -whereby the action of the dash pot will be very sluggish. After the dash pot has adjusted itself to the vehicle load it will become practically inactive and will impairl none of the functions of the shock absorber, the dash pot then becoming practically the same as a direct connection for the member 5 to the bracket 10. This automatic adjusting device takes the place of a turn buckle or similar manually operated adjusting means and it may be applied in various forms and to a. large variety of shock absorbers, and another very compact construction of this improvement is illustrated in Figs. 1, 4 and 5, which construction `will now be described.

The shock absorber proper illustrated in Figs. 1,4 and 5, is similar to that shown in Figs. 2 and 3, comprising the members 4 and 5 hinged together aty 6, the free end of the member 4 being pivoted at 7 to the bracket 8 on the frame 1. On the member 4 is a wedge piece 17 arranged concentric vwith the pivot 6 and tapering from both ends toward its middle portion as in Fig. 2. Frictionally engaging the sides of the Wedge piece 17 are the friction lining pieces 1G on the plates 14 and 15, which plates are yieldably pressed together by the spring 18 on the posts 19 and adjusted by the nuts 20. Enlargements 21 of the posts 19 are also provided -to separate the plates sufficiently near the middle of the Wedge piece so that very., little if any frictional action -takes place at this point. 15, in this form of the invention forms a continuation of the free end of the member 5 and may be integral therewith. In the present form of the invention, insteadof connecting the free end of the member 5 with thel bracket '101l through a dash pot of the type illustrated in Fig. 2, this connection is made through a wing dash potl 22a Aand an arm 26, which arm is rectly to the bracket 10a as at 9u.

Referring more particularly to Figs. 4 and 5 itl will be'seen that the member 5a comprises a` shallow cylinder 23 having central hub portions 30 and 31 inWhieh the bolt 32 forming the hinge 6a is journaled. The outer end of thehub 30 is closed but the bolt 32 extends through t-he hub 31 which is provided With a packing ring .3 and packing-34 afnd is keyed to the arm 26a. The outer surface 35 of the hub 31 is machizied to receive the hub 3G of the relatively movable member 4 and this hub 36 is held thereon by a nut 37 and Wasl1er38. Frie-I tion Washers 39 are also arranged on both sides of the hub 36 to keep the parts tight and prevent rattling. The open end of the cylinder is closed by a disk 43 threadedinto it at 44 and locked in adjusted position by a dog 45 taking in the notches 46, this disk being shown as' formed integral with the hub 31. Suitably secured in the cylinder 231 by screws 40 are'three abut-ments 41 having radial chambers 42 between each pair. rThe pivoted diwhich are slightly smaller than the chambers just the middle point'of least resistance of tive to one of the vehicle parts.

.end walls of the chambers 42 through' `which 'position of the axle.

comprising two relatively movable elements bolt 3Q is provided with radial pistons 24 4Q andare adapted to oscillate therein. -The remaining space in the chambers 42 is filled with thick graphite grease or other unctuous material inserted through the opening d? closed by the plug 48. The abutments 'All and thrl pistons .Qta are formed with circumferential channels it) and 5G respectively, whereby the bolt 32 may have a slight os cillatory movement relative to the cylinder 23a as it slowly displaces thethick grease through said channels. Bythus providing channelsin both theipist0ns-and thev abutments the single lilling opening will serve for filling the entire cylinder. Shallow grooves 5l are also provided in the radial the grease may be ldisplaced bythe piston as it approaches'these end Walls.

From the above it will` be observed that the arm 26ahas .a somewhat limited movement relative tothe member 5a through the wing dash pot/22, but all sudden movements of the'arm 26a imparted to it by the axle 2 Ato which it is pivoted through the rigid bracket 10a, are immediately conveyed to t-he member 5a which carries the `friction plates 14 and 15.v Thus the sudden vibrations of the spring hung axle are resisted by the shock absorber in the usual manner and it is only when the axle 2 alters its mean position relative to the frame l that the wing 'dash pot comes into. play, and then this dash pot serves to automatically readthe shock absorber to this changed meanv l Although the automatic adjusting teaturev of this invention has been shown as attached to a particular Jcrm of shock absorber, in.

will be understod that it isnot limited to applied' to various other forms offshock absorbers., and -it may be so combined With certain forms ofshock' absorbers a-nd so altered as to assist inthe Work of resisting the spring actionand thusbecome an auxil' iai-y to the inain absorber" While still maintaining its function of adjustment for the main absorber.

Having thus described my invention, what I claim is,- i

l., The combination with a shock absorber4 having a given range of action, of means for automatically varying said range rela- 2. The combination with a shock absorber capable ot a given range of operation.I and means for connecting said elements to the vehicle partsyof means for automatically shifting said range relative to one. otf said connecting means,

3. The combination with a shockabsorber having a point of leastI resistance which is constant relative to one of the vehicle parts, of means for automatically varying said point relative to the normal position oi the other vehicle part.

Li, rIhe combination with a shock absorber havi'ling a point of least resistance, lof means for automatically varying said point relative to the normal position of the vehicle parte, said means comprising a 'dash pot connected tb the shock absorber. 7

5. In a shock' absorber having three relatively movable parts, retarding means be-Y tween two of said parts and a more sluggish retarding means between oneI of. said two parts and the third part.'

6. The combination ivith t'wo s}niri, gj-co1rl nected elements having a shiftable mean poe sition, of a shock absorber between said elements, and means for automatically main taining the point of least resistance of said shock absorber in correspondence with said mean position.

7. The combination With two spring-connected elements and a shock absorber between said element-s, of a dash-pot arranged in one of the connections from said shock absorber to said elements.-y

8. In a motor vehicle, the combination with the frame, the axle, andthe springs between the frame and aide, eta-shock ab sorber between said trame and axle, and a dash-pot arranged in one Yof the connections from said shock absorber to the vehicle 'i parts.

9. The combination with a shock absorber t having a given range of action, of means for automatically uarying said range relative to one of the vehicle parts comprising a dash-pot operated by the vibrations transmitted to the shock absorber.

10. A shock, absorber comprising two members pivoted together', a. Wedge shaped piece on one of said members, spring-pressed plates on 'the lother of said members adapted to frictionally engage said Wedge 4piece on opposite sides. a dash-pot connected to one of said 1neinbers, and means for con-Y necting said dash-pot and the opposing member respectively to relatively movahleparts of a vehicle.

1l.- A shock yabsorber comprising two members piuot'ed together, a wedge lshaped iece on one of said members, spring-pressed plates on the other' of said members adapted to frictionally engage said Wedge piece on 129 opposite sides, a cylinder rigidly connected to one of said members and arranged concentric with'itspivot, an abutment therein, a Wing piston having al limited ('scillatory movement in said cylinder, a shaft' conf,- rnected to said piston, and means for con l2. A shock absorber comprising a mern- 15,

v.second member bei-"-formed with a cylinder having hubs, a l `material to be displaced by the piston as the journaled on one ofy said hubs, retardingdevices between said members, a bolt -journaled concentric with said cylinder, means for permitting a limited sluggish oscillatory movement between "the v bolt and the cylinder, and means for conneeting said second member and said bolt respectively to ditl'erent parts of the vehicle.

lA ber formed with. a pair of spring-pressed friction plates and a cylinder having hubs, a second member jourualed on one of said hubs and having a friction arm adapted to oscillate frictionally between said plates, a holt journaled concentric with said cylinder, means for permitting a limited sluggish oscillatory nnn'ement between the bolt and the cylinder, and means for connecting said second member and said bolt respectively to different parts of the vehicle.

14. A' shock absorber comprising a member formed with a pair of spring-pressed friction plates and a cylinder having hubs7 a second member journaled on one of said hubs and having a friction arm adapted to oscillate frictionally between said plates, a bolt journaled concentric with said cylinder, means for permitting a limited sli'lggish oscillatory movement between the bolt and the cylinder, a connecting arm attached to said bolt, and means for comiecting said .second member and said connecting arm respectively to-ditferent parts of the vehicle.

15, The combination ina shock absorber, of friction elements, and a dash pot comprisinggr a cylinder, der, an oscillating piston. in the cylinder having wings operating in the chambers between the abutments, packing material in the cylinder to retard the oscillations of the piston. and means to permit said packing material to be displaced by the piston as the latter nears the abutments.

l5. The combination in a shock absorber, of friction elements, and a dash pot com'- prising a c vlimler, abutments in the cylinder,l an oscillating piston in the cylinder 4having wings ope `ating in the chambers between the abntments, and packing material in the cylinder to retard the oscillations of the piston, said abutments having grooves in their end walls to permit said packing .shock absorber comprising a mem-` abutments in the cylin I latter nears the abutments.

17. A shock absorber comprising a member con'lposedV of a cylinder and a pair ofv springapressed friction plates extending radially therefrom, another member jour- 'nal'ed on the hub of said cylinder and having a friction arm adapted to slide between and frictionally engage said plates whereby relative oscillation of said members is resisted by friction, an abutment in'said cylinder, a wing piston liournaled to oscillate be tween the walls of said abutment, packing materialin the cylinder to resist the oscillations of the piston, means permit'til'igl the slow passage of said packing material from one side of the piston to the other, and an arm attached to said piston for connecting it with the. vehicle.

18. A shock absorber comprising friction elements, and a dasl1-pot connecting one of said elements with the vehicle.

19. The combination .with a shock absorber havingr a point `of least resistance, of means for automatically varying said point relative to the normal position .of the vehicle parts. said variation being accomplished without lost motion atA the ends of the vibra tory strokes.

20. The combination with a shock. ab;

sorber having.r a point of least resistance, and means progressively increasingthe resistance from said point, of means for automatically.varying said point relative to the normal position of the vehicle parts.

21..1lr shock members pivotcd together at a common point, a dash-pot between two of said members, and a frictional retarding device between another two of said members.

22A shock absorber comprising three members pivoted together at a common point, a wing dash-pot arranged 'at the common point between two of said members, and a coinrentrically arranged frictional retarding` device between another two of said members.

In testimony whereof I affix my signature in presence of two witnesses.

. ALLEN LOOMIS.

Y Vtfit'nesses:

F. N. HnAlcN, C. I. DALE.

absorber comprising threel 

